Within a(n) , there is a level of economic integration that involves the use of a common currency, harmonization of members' tax rates, and a common monetary and fiscal policy

Within an economic and monetary union, there is a level of economic integration that involves the use of a common currency, harmonization of members' tax rates, and a common monetary and fiscal policy .

Explanation:

An economic and monetary union is a form of economic integration of states, including the common market, harmonization of economic policy (or common economic policy) in several areas, and monetary union (a common currency or at least fixed exchange rates between Member States). It is the fifth phase of economic integration.  

Sometimes a monetary union is seen as either the starting point of an economic (and monetary) union, sometimes - more often - than its completion. Since there is also a monetary union without a common market and / or harmonized economic policy, the concepts of "economic and monetary union" and "monetary union" need to be differentiated.  

A typical example is the European Union's Economic and Monetary Union.

answer; i believe the correct answer is (a) purchase of treasury stock;